Sunday, February 17, 2013
Auditorium/Exhibit Hall C (Hynes Convention Center)
Background: Current educational practices attempt to raise student interest in STEM disciplines, improve understandings of science as a process, and demonstrate the connection of science to society. In order to facilitate these goals, a risk assessment project for upper-level science students was developed in partnership with international development organizations in Cambodia and Laos. Students from two science courses, and from one independent research project, measured arsenic concentrations in source clay from organizations that produce ceramic water filters. Arsenic intake and effects were estimated to provide a student-driven risk assessment that provided input for the providing agencies on which clay sources had lower arsenic levels.
Methods: A series of laboratory exercises was developed which stepped students through a risk assessment approach to the evaluating the danger of contaminants in a "real world" situation. Students compared arsenic levels measured in clay samples using cold vapor atomic absorption spectrophotometry, with established benchmarks for health effects. A rubric was implemented for one class to assess items in student understanding of the nature of science.
Results: Arsenic in clay ranged from 0.72 to 19.9 ppm. Higher concentrations of arsenic were found in samples collected close to the Mekong River. Rates of ingestion of arsenic through drinking water were estimated at less than EPA and WHO health standards. Rubric assessment of student learning for one course indicated particularly high ratings (average 4.6 on a 5 point scale) in understanding of the social and cultural relevance of the nature of science. Students also received high ratings for items of content knowledge, analysis, and synthesis.
Conclusions: Upper level science students successfully provided needed information to two international development agencies on arsenic in their clay sources. Incorporation of “real world” partnerships with international development agencies provided a unique and socially-relevant connection for students. These experiments successfully engaged students, resulted in high scores for measures of science understanding, demonstrated the international relevance of science, and provided needed data for organizations that work on the manufacturing of clay water filters.
Methods: A series of laboratory exercises was developed which stepped students through a risk assessment approach to the evaluating the danger of contaminants in a "real world" situation. Students compared arsenic levels measured in clay samples using cold vapor atomic absorption spectrophotometry, with established benchmarks for health effects. A rubric was implemented for one class to assess items in student understanding of the nature of science.
Results: Arsenic in clay ranged from 0.72 to 19.9 ppm. Higher concentrations of arsenic were found in samples collected close to the Mekong River. Rates of ingestion of arsenic through drinking water were estimated at less than EPA and WHO health standards. Rubric assessment of student learning for one course indicated particularly high ratings (average 4.6 on a 5 point scale) in understanding of the social and cultural relevance of the nature of science. Students also received high ratings for items of content knowledge, analysis, and synthesis.
Conclusions: Upper level science students successfully provided needed information to two international development agencies on arsenic in their clay sources. Incorporation of “real world” partnerships with international development agencies provided a unique and socially-relevant connection for students. These experiments successfully engaged students, resulted in high scores for measures of science understanding, demonstrated the international relevance of science, and provided needed data for organizations that work on the manufacturing of clay water filters.